Congratulations, yesterday you were an individual contributor, today you are a manager!!!
Now you have direct-reports - you are usually responsible for assigning them work and managing their performance of those tasks —you're their boss. The hard part of the boss job is the “managing performance” part.
You and your direct reports are now partly dependent on each other to achieve success. When they succeed, you succeed. And they'll succeed with your mentoring. One of your goals as a manager should be to teach someone how to do your job - so you can get promoted to do an even more important job. Your next most important goal is to recognize those who are not contributing, work to get them on the right track - or to move them out is they can’t learn to do the job. Harsh sounding maybe, but that’s part of being the boss! There are several good articles on mentoring available, they all say about the same thing. Here’s one I think is to the point and accurate: https://fairygodboss.com/articles/how-to-be-an-effective-business-mentor.
It is difficult when you first become a manager to remain friendly, but stop being friends with the folks who used to be your co-workers and are now your direct reports. However, it is one of the most important steps you need to make. This move should not be abrupt, because then your former co-workers will think you got the big-head along with the promotion. Ease yourself out of those after hour sessions of whine and cheese and while you always have a friendly greeting for everyone, if you stop to chat for a minute, it’s about the weather or traffic and not the current office gossip.
A sad fact about some people and promotion - they become Little Hitlers. They are so afraid that they are not going to make the grade as a boss that they become dictatorial, and seem to forget that their direct reports are people, too. Good managers don’t get all wrapped up in everybody punching in 5 minutes before they are to start working and they don’t stand at the door taking notes about what time their direct reports come back from lunch! (Here’s a great article by Susan Lucas about that! https://www.inc.com/suzanne-lucas/10-things-managers-should-stop-worrying-about.html) Good managers do take note of who’s struggling with a task, who never turns in a project on time and who looks as though they don’t feel well. There’s no reason you can’t ask an employee to step into your office and behind closed doors, ask if they feel well, or whether they are having trouble with a task. Also, there is a very good reason why you should be checking with an employee who is consistently not turning work in on time, because that employee needs to be on a plan that helps them get their work done, and if that doesn’t work, they need to be on a warning plan that will move them out.
This is where a new manager could use a warning - 61% of workplace bullying comes from bosses. How you approach poor work, general tardiness and some of the other poor habits employees can develop is very important. Glaring, yelling, having a tantrum are indicative of immaturity - not good managing. Your management style directly affects your direct reports, their willingness to go the extra mile when it’s needed and whether they stay with you or move on because you are ineffective, rude, overly familiar, or to put it bluntly - a bad boss.
You can be a good manager. You were promoted because someone felt that you had the chops for the job. Take your time - enjoy the feeling and remember, you can’t go wrong if you do your best to do what’s right.